This invention relates to insulative apparel for the foot and more specifically to an insulator to be detachably secured atop the forward portion of the boot of a cross-country (Nordic) snow skier to provide added protection to the toes and foot from cold air and snow.
The motions of a skier's foot during cross-country skiing are such that they require a flexible boot, the toe of which is attached to the ski's midpoint by means of a binding as illustrated in FIGS. 1, 2, 3, and 4. The common pin binding 8 includes a bail 9 which securely clamps an extension 7 of the sole of the boot 6 into the binding 8 and thus onto the ski 10. The binding 8 also has metal pins 11 (see FIG. 4) which fit into holes in the underside of the sole extension 7 to help hold the boot in position.
The cross-country ski boot which meets the above requirement of flexibility is often necessarily deficient in built-in insulation. Many cross-country skiers suffer extreme discomfort and even frostbite of the toes when wearing well-made lined boots and thick socks. The toes and other extremities are especially susceptible to chilling because of physiological mechanisms which reduce circulation to them in order to conserve heat for more vital body organs.
The inclusion of multiple layers of socks between the foot and the boot has the limitation that it seriously restricts toe movement, and further reduces blood circulation to the toes. Thus, adding more layers of socks may result in colder toes. The substitution of a layer of thin plastic socks may reduce heat loss through evaporative cooling; but, considerable amounts of undissipated perspiration from sustained exercise is uncomfortable and disconcerting to many people.
A sound approach to the problem of maintaining the warmth of the feet and toes is that of the addition of insulation onto the exterior of the boot. Such a means does not have the disadvantages mentioned above, namely restriction of toe movement or retention of perspiration. Furthermore, this approach offers versatility; the insulation may be easily applied or removed as necessary.
Previously devised foot muffs, over-boots, and shoe protectors do not seem appropriate for the purpose of insulating the toes of a cross-country skier while accommodating the structural requirements of the present day ski boot and binding. Particularly inappropriate for the stated purpose is the inclusion of soles in the garment. These could interfere with fitting the boot in the binding 8, alignment of binding pins 11 with holes in the boot sole extension 7, etc. Furthermore, the installation over the ski boot of an overgarment with soles requires the removal of the boot 6 from the binding 8. Reinstallation of the boot in the binding usually requires removal of snow from the binding and boot sole prior to realignment of the holes in the boot sole extension 7 with the binding pins 11. These operations are obviously an inconvenience to the skier.
Accordingly, the object of my invention is the provision of a conveniently attachable and detachable durable insulator specifically designed to insulate the toes and foot while accommodating the structural requirements of a cross-country ski boot and binding. Further objects will become apparent from a consideration of the drawings and ensuing description thereof.